PIK3CA hotspot mutations and cyclooxygenase-2 expression in ovarian clear cell carcinomas: a close association with stromal features.

Ovarian clear cell carcinomas (CCCs) have 2 distinct stromas: a hyalinized/mucoid stroma and a plasma cell-rich inflammatory stroma. Clinically, CCC is the most common ovarian cancer associated with thromboembolism. Recent studies suggested a potential role of PIK3CA mutation in the cyclooxygenase (COX) pathway, which mediates inflammation or hemostasis. In the present study, 54 ovarian CCCs and 3 CCC cell lines were analyzed for PIK3CA hotspot mutation and COX-2 expression with special reference to stromal features. Among the 54 CCCs, 20 (37.0%) and 8 (14.8%) were classified as CCCs with a hyalinized/mucoid stroma and an inflammatory stroma, respectively. PIK3CA mutation was identified in 11 (55%) of the 20 CCCs with a hyalinized/mucoid stroma, but not in any of the 8 CCCs with an inflammatory stroma. In contrast, COX-2 expression was frequent in CCCs with an inflammatory stroma (1/20 [5%] versus 7/8 [87.5%], respectively). Such a relationship between the PIK3CA mutation, COX-2 expression, and stromal features was repeated in the 3 CCC cell lines. Thromboembolism was noted in 9 (16.7%) of the 54 CCC patients, and it was more frequent in CCCs with a hyalinized/mucoid stroma (7/20 [35%]) than in those with an inflammatory stroma (0/8 [0%]). In conclusion, there is a difference in PIK3CA mutation, COX-2 expression, and paraneoplastic thromboembolism between CCCs with a different stroma. It is suggested that a different stromal feature, either hyalinized/mucoid change or inflammation, represents a different molecular genetic background or hemostatic potential in ovarian CCCs.

DICER1 hotspot mutations in ovarian Sertoli-Leydig cell tumors: a potential association with androgenic effects.

Sertoli-Leydig cell tumors (SLCTs) are representative of androgenic ovarian tumors, and they show diverse histologic differentiation, including heterologous differentiation. Genetically, SLCTs are characterized by the presence of DICER1 mutations. In the present study, we analyzed the correlation between somatic DICER1 hotspot mutations and clinicopathological features in 10 ovarian SLCTs. Six of the 10 (60%) SLCTs harbored a DICER1 hotspot mutation. Five of the 6 DICER1-mutated SLCT patients showed androgenic manifestations, including amenorrhea and hirsutism, and 4 of the 6 were associated with the significant elevation of serum testosterone. In contrast, none of the 4 DICER1 wild-type SLCT patients showed virilization. The patient age at diagnosis was lower in those with DICER1-mutated SLCTs (average, 24.7; range, 17-43) than in those with DICER1 wild-type tumors (average, 64.8; range, 47-77). Histologically, heterologous differentiation was found in 4 SLCTs, all of which were DICER1 mutant. Heterologous components included gastrointestinal-type mucinous epithelium (n=3), carcinoid (n=1), and rhabdomyosarcoma (n=1). In the latter, the rhabdomyosarcomatous component was dominant to the SLCT component. In summary, DICER1 hotspot mutations are closely associated with androgenic effects in ovarian SLCTs. It is suggested that DICER1 mutations are involved in the dysregulation of sex hormone synthesis in SLCT patients. Somatic DICER1 hotspot mutations are more common in SLCT patients during the reproductive years than in those during the postreproductive years. DICER1 hotspot mutations may support the pathological diagnosis of SLCTs in cases wherein the heterologous component overwhelms and masks the SLCT component.

Expression of P450 Aromatase in Granulosa Cell Tumors and Sertoli-Stromal Cell Tumors of the Ovary: Which Cells Are Responsible for Estrogenesis?

Granulosa cell tumors are representative of estrogenic ovarian tumors, and some Sertoli-stromal cell tumors are also estrogenic. The exact cells that are responsible for estrogenesis, however, have yet to be identified. In the present study, 25 sex cord-stromal tumors (20 granulosa cell tumors, 4 Sertoli-Leydig cell tumors, and a Sertoli cell tumor) were immunohistochemically examined for expression of P450 aromatase, which is critical for estrogenesis. All of the tumors had been evaluated for estrogenic function, including contemporaneous endometrial hyperplasia and/or elevation of serum estradiol. Eleven of 14 estrogenic granulosa cell tumors showed sparse or aggregated immunoreactivity for aromatase, whereas 5 of 6 nonestrogenic tumors did not. Aromatase was selectively expressed by plump granulosa cells with eosinophilic or vacuolated cytoplasm, resembling luteinized granulosa cells. Such a localization of aromatase is analogous to that in normal ovaries. Aromatase expression in primary tumors was recapitulated by recurrent tumors. In Sertoli-stromal cell tumors, either undifferentiated plump cells or well-differentiated Sertoli cells expressed aromatase. In conclusion, the expression of P450 aromatase corresponds to specific cell morphology in sex cord-stromal tumors, including recurrent tumors. Aromatase status in granulosa cell tumors provides helpful information on whether serum estradiol could be a marker for recurrence.

Ovarian clear cell carcinoma with plasma cell-rich inflammatory stroma: a clear cell carcinoma subgroup with distinct clinicopathological features.

AIMS: Ovarian clear cell carcinoma has a unique stroma. Although a hyalinized or mucoid stroma is more common, the stroma sometimes shows a dense inflammatory infiltrate, simulating a dysgerminoma. The aim of this study was to analyse the character and significance of the inflammatory stroma. METHODS AND RESULTS: Twelve of 60 (20%) clear cell carcinomas showed an inflammatory stroma. The inflammatory stroma and hyalinized/mucoid stroma were mutually exclusive. Inflammatory cells were predominantly composed of CD138-positive plasma cells. As compared with the non-inflammatory cases, the epithelial component frequently showed a solid growth pattern and immunoreactivity for cyclooxygenase-2, one of the critical proinflammatory enzymes (P < 0.005). These findings were repeated after heterotransplantation of three clear cell carcinoma cell lines into athymic nude mice. In particular, xenografts of one cell line (JHOC-5) were infiltrated by mature plasma cells, indicating that plasma cell differentiation was stimulated by JHOC-5 cells, independently of T lymphocytes. Clinicopathologically, the frequency of International Federation of Gynaecology and Obstetrics stage III was higher in the cases with an inflammatory stroma than in those without it (P < 0.01). CONCLUSIONS: Clear cell carcinomas with an inflammatory stroma constitute a distinct clinicopathological subgroup. It is strongly suggested that tumour cells themselves are responsible for inducing inflammation and stimulating plasma cell differentiation in a paracrine manner.

How does secondary neoplasm arise from mature teratomas in growing teratoma syndrome of the ovary? A report of two cases.

Development of secondary neoplasm in mature teratomas is a long-term potential risk in growing teratoma syndrome (GTS) of the ovary. The origin or histogenesis of the secondary neoplasm, however, is scarcely understood. We herein report two cases of GTS that began secondary neoplastic change 10 and 22 years after initial presentation. In one case, microscopic carcinoids were scattered over various mature elements derived from three germ cell layers: some were close to the intestinal-type glands or adipose tissue and others lay in the glia. This implies that these carcinoids multicentrically originated from pluripotent stem cells that had been latent in various mature tissues. In contrast, the other case had only one focus of intestinal-type tubular adenocarcinoma, measuring 5 mm in diameter, adjacent to the intestinal-type glands. Malignant transformation of intestinal-type glands is most likely to account for this adenocarcinoma. In both cases, peritoneal mature teratomas also contained foci of endometriosis, almost exclusively in their glial components. In conclusion, the present cases suggest two diverse histogenesis of secondary neoplasm in GTS and a specific role of glia in the development of endometriosis in peritoneal teratomas.

Hyalinized stroma in clear cell carcinoma of the ovary: how is it formed?

Ovarian clear cell carcinoma often shows stromal hyalinization. The main constituents of hyalinization are basement membrane materials, including laminin and type IV collagen. Although it is known that clear cell carcinoma cells produce these materials, it remains unclear whether they can form hyalinized stroma by themselves or if cooperation with stromal cells is required. In the present study, we first reviewed 35 surgical specimens for the pattern of early hyalinization. It occurred either in a globule-like pattern or in a circumferential pattern. In the former, compact hyaline globules abruptly appeared within tumor cell aggregates. In the latter, hyalinized materials appeared around the preceding spherule-like mucoid spaces among tumor cells. In either pattern, hyalinization is most likely to begin in the intercellular spaces among tumor cells, where stromal cells rarely intervene. To verify this, 2 ovarian clear cell carcinoma cell lines (JHOC-5 and HAC-2) were analyzed in vitro. Each cell line was monocultured in suspension: if any deposition occurred in floating multicellular aggregates, it should be in the intercellular spaces. Deposition of type IV collagen occurred in a globule-like pattern (JHOC-5) or a circumferential pattern (HAC-2) within multicellular aggregates, and it developed into a structure comparable with the hyalinized stroma in surgical specimens. Intercellular deposition of type IV collagen was reproduced by culture in 3-dimensional type I collagen gels. All of these findings showed that clear cell carcinoma cells themselves form hyalinized stroma by depositing self-made basement membrane materials in the intercellular spaces.

Alternate mucoid and hyalinized stroma in clear cell carcinoma of the ovary: manifestation of serial stromal remodeling.

The stroma in ovarian clear cell carcinoma often shows alternate mucoid and hyalinized change. The hyalinized stroma is recognized to be an aberrant deposition of basement membrane material produced by tumor cells. The mucoid stroma, however, has drawn far less attention, and its significance remains unclear. We examined 60 ovarian clear cell carcinomas for the distribution and nature of the mucoid stroma. For comparison, 125 other surface epithelial ovarian tumors were examined. Twenty-nine of 60 (48%) clear cell carcinomas showed a mucoid stroma, either focally (21 cases) or diffusely (8 cases). The mucoid stroma in clear cell carcinomas was distinct from that in other surface epithelial tumors as follows: it showed a compact spherule-like appearance, commonly occupying the cores of small papillae. It also exhibited a cribriform pattern, resembling that of adenoid cystic carcinoma. It was rarely associated with stromal cells, despite the presence of abundant glycosaminoglycan including hyaluronan. Alternatively, it was strongly associated with hyalinized stroma. Among 40 clear cell carcinomas that had at least one type of stroma, 26 (65%) had both, either concomitantly or separately. The mucoid stroma tended to attenuate if the hyalinized stroma developed. In vitro, a clear cell carcinoma cell line, HAC-2, formed a spherule-like structure containing hyaluronan in the center, and a significant amount of hyaluronan was detected by latex agglutination immunoturbidimetry, indicating that HAC-2 itself has the potential to produce hyaluronan. All of these facts indicate that the spherule-like mucoid stroma and hyalinized stroma represent different phases of the stromal remodeling process, which is promoted by the deposition of different extracellular matrices produced by clear cell carcinoma cells. The spherule-like mucoid stroma and hyalinized stroma are considered complementary diagnostic signatures of ovarian clear cell carcinoma.

Growing teratoma syndrome of the ovary after fertility-sparing surgery and successful pregnancy.

BACKGROUND: Growing teratoma syndrome (GTS) is rare and is defined as an enlarging mature teratoma that arises during or after chemotherapy for a malignant germ cell tumor, with normalization of previously elevated serum tumor markers. CASE: A 30-year-old nulliparous Japanese woman was diagnosed as having a stage IIIa immature teratoma. After fertility-sparing surgery, she received 4 cycles of chemotherapy consisting of cisplatin, etoposide and bleomycin. Thereafter, she successfully gave birth twice. Eight years after the initial surgery, a mass mimicking an adrenal tumor was resected laparoscopically. Surgical specimens revealed a mature teratoma, and she was diagnosed as having GTS postoperatively. CONCLUSION: Clinicians should consider that GTS may present late, even after pregnancy. Therefore, long-term follow-up of patients treated for ovarian immature teratoma should be mandatory.

Familial amyotrophic lateral sclerosis: a SOD1-unrelated Japanese family of bulbar type with Bunina bodies and ubiquitin-positive skein-like inclusions in lower motor neurons.

We describe a new family with adult onset amyotrophic lateral sclerosis (FALS), in which the disease was characterized clinically by relatively rapid progression of bulbar symptoms. Gene analysis of Cu/Zn superoxide dismutase (SOD1) performed in one patient showed no mutations. Autopsy of another patient demonstrated degenerative changes restricted to the upper and lower motor neuron systems; no evident changes were observed in the posterior column, Clarke's column or spinocerebellar tracts. The presence of Bunina bodies and ubiquitin-positive skein-like inclusions in the lower motor neuron was of considerable interest. Cases of FALS with such pathological features are quite rare in the literature. Identification of the gene responsible for the disease is desirable in order to shed further light on the molecular pathology of not only familial, but also sporadic, ALS.

Corticobasal degeneration with focal, massive tau accumulation in the subcortical white matter astrocytes.

We report two sporadic cases of tauopathy with unusual neuropathological features. The ages of the patients at death were 86 and 74 years, and the disease durations were 4 and 3 years, respectively. The former patient showed progressive dementia and amyotrophy (autopsy revealed that severe cervical spondylosis was responsible for the amyotrophy), and the latter showed progressive parkinsonism and dementia. The essential brain pathologies were similar to each other; although ballooned neurons and astrocytic tau lesions (astrocytic plaques) were present in the affected cerebral cortex, the most striking finding was focal, much heavier accumulation of tau in the subcortical white matter. Moreover, double-labeling immunostaining, as well as Gallyas-Braak electron and AT8 immunoelectron microscopic studies strongly suggested that in the affected subcortical white matter, the accumulation of tau occurred mainly in the astrocytic processes. In the latter patient, for whom frozen brain tissue was available, immunoblotting of insoluble tau revealed a pattern compatible with that obtained from brain affected by typical corticobasal degeneration (CBD), and gene analysis of tau revealed no mutations, with a H1 haplotype. Finally, in both cases, the pathological diagnosis of CBD was considered to be appropriate. However, the tau pathology affecting the subcortical white matter astrocytes was very unusual for the disease.

Involvement of adenomatous polyposis coli (APC) gene in testicular yolk sac tumor of infants.

The pathogenesis of testicular yolk sac tumor (YST) of infants is still unclear. Infantile YSTs rarely show isochromosome 12p or aneuploidy, which are common in adult germ cell tumors. On the other hand, recent epigenetic studies suggest the involvement of some tumor suppressor genes, including the adenomatous polyposis coli (APC) gene. In the present study, we examined 10 infantile pure YSTs for mutation, allelic loss, promoter methylation, and protein expression status of the APC gene to evaluate whether the APC gene plays a significant role in the pathogenesis of infantile YSTs. Loss of heterozygosity at 5q21, where the APC gene is localized, was detected in at least 3 (30%) of the 9 YSTs examined. None of the 10 YSTs showed mutations. Promoter methylation was detected in 7 (70%) of the 10 YSTs; among 7 YSTs showing methylation, 3 YSTs also harbored loss of heterozygosity at 5q21. Immunohistochemically, 8 infantile YSTs did not express the APC protein, whereas 2 YSTs without showing APC methylation, as well as germ cells of normal infantile testes, expressed this protein in the cytoplasm. These data indicate that inactivation of the APC gene, by allelic loss and/or promoter methylation, is related to the occurrence of infantile YSTs.

Successful surgical treatment of angiosarcoma of the spine: a case report.

STUDY DESIGN: Case report. OBJECTIVES: To report primary angiosarcoma of the T8 vertebra, which was successfully managed with en bloc spondylectomy and postoperative chemotherapy. SUMMARY OF BACKGROUND DATA: To the best of our knowledge, the present case is the first documented example of successful treatment of angiosarcoma of the spine. METHODS: Angiosarcoma of the eighth thoracic vertebra was diagnosed in a 48-year-old man with impending neurologic deficit. Imaging findings revealed a nonspecific high-grade lesion. A total spondylectomy of T8 by en bloc resection was performed. The defect of the vertebral body was reconstructed with a apatite-wollastonite glass ceramic prosthesis; moreover, the T6-T10 vertebrae were instrumented by the pedicle screw, hook and rod system. The histologic diagnosis of the excised specimen was high-grade angiosarcoma. Postoperative chemotherapy was implemented to prevent local recurrence and distant metastasis. RESULTS: No sign of local recurrence or metastasis was evident 5 years after surgery. CONCLUSION: This case is the first documented example of successful treatment of angiosarcoma of the thoracic spine. Radiologic findings were nonspecific; consequently, correct diagnosis was established by pathologic examination. Immediate, aggressive operative treatment and postoperative adjuvant chemotherapy afforded a satisfactory outcome.

Expression of a transcription factor, SOX9, in Sertoli-stromal cell tumors of the ovary.

Two cases of ovarian Sertoli-stromal cell tumor were examined for expression of a transcription factor, SOX9, which plays an essential role in Sertoli cell differentiation, downstream of Sry, as in the testis. By reverse transcriptase polymerase chain reaction, SOX9 mRNA was expressed in both tumors, despite the absence of Sry. These findings suggest that SOX9 expression probably plays some role in Sry-independent testicular differentiation in ovarian Sertoli-stromal cell tumors.

Carcinosarcomas (malignant mullerian mixed tumors) of the uterus and ovary: a genetic study with special reference to histogenesis.

The histogenesis of carcinosarcomas (malignant mullerian mixed tumors) of the female genital tract is still not completely understood. In the present study, several different molecular pathologic techniques were applied to determine the histogenesis of 15 uterine and ovarian carcinosarcomas. The patterns of X-chromosome inactivation and the presence of p53 and K-ras mutations were analyzed in the carcinomatous and sarcomatous components. Microsatellite analysis was also performed. Ten tumors were monoclonal, one was biclonal (collision tumor), and another was probably biclonal; the other three were of indeterminate histogenesis. These data indicate that most uterine and ovarian carcinosarcomas are monoclonal.

Mucin expression in nonneoplastic and neoplastic glandular epithelia of the uterine cervix.

Although it is well known that the uterine cervix contains mucin-producing glandular epithelium, only a few studies have described the changes in mucin that accompany malignant transformation. In this study the authors evaluated the characteristics of mucin expression in the normal endocervical epithelium and mucinous and endometrioid adenocarcinomas of the uterine cervix. The normal endocervical epithelium was characterized by predominant sulfomucin and MUC1 expression in all sites and MUC5AC expression in the surface epithelium, while MUC2 was not detected at all and pyloric gland type mucin (using antibody HIK1083) was detected in less than 1% of cases. Cervical adenocarcinomas, especially mucinous adenocarcinomas, showed marked variability in mucin expression that included mucins of pyloric gland and intestinal type.

Hypermethylation of the RUNX3 gene promoter in testicular yolk sac tumor of infants.

Testicular yolk sac tumor (YST) of infants is biologically distinct from its adult counterpart. Cytogenetically, YSTs in infants generally lack i(12p), which is highly characteristic of adult germ cell tumors (GCTs), whereas they frequently show a deletion of 1p36, indicating that the loss of a certain gene(s) in this region is an important event in the pathogenesis of infantile YSTs. In the present study, we examined 10 testicular YSTs from infants for promoter methylation status of the RUNX3 gene, localizing in 1p36.1, and loss of heterozygosity (LOH) in this region, on the presumption that RUNX3 acts as a tumor suppressor. Methylation of RUNX3 and LOH at 1p36.1 were detected in 8 of 10 (80%) and 6 of 8 (75%) infantile YSTs examined, respectively. All six cases harboring LOH showed RUNX3 methylation. In contrast, 0 of 12 adult GCTs showed RUNX3 methylation, and LOH at 1p36.1 was less frequent (1 of 6 cases: 16%) in adult GCTs. There is a significant difference in RUNX3 methylation between these 2 groups (P < 0.001). In normal testes of the young group, RUNX3 methylation was not detected. These results strongly suggest that RUNX3 is one of the tumor suppressors involved in the pathogenesis of testicular YSTs in infants.

Neurofibromin and NF1 gene analysis in composite pheochromocytoma and tumors associated with von Recklinghausen's disease.

Composite tumor of pheochromocytoma and neuroblastoma, or ganglioneuroma, or ganglioneuroblastoma (composite pheochromocytoma), also known as mixed neuroendocrine and neural tumor, are sometimes combined with neurofibromatosis type 1 (NF1). To better understand the relationship between NF1 and composite pheochromocytoma, an immunohistochemical study using anti-neuro-fibromin that is an NF1 gene product and DNA sequence of NF1 Exon 31 were carried out in five cases of composite pheochromocytoma and in various tumors from five patients with NF1. Neurofibromin was not expressed in Schwann cells and sustentacular cells of composite pheochromocytomas and was very weakly or negatively expressed in neurofibroma of NF1 patients. However, it was strongly expressed in ganglionic cells and pheochromocytoma cells of the composite pheochromocytomas and also in mucosal ganglioneuromas, a gangliocytic paraganglioma, and in pheochromocytomas from the patients with NF1. Although there was no mutation in NF1 Exon 31, it could not be ruled out that there were mutations in other sites of the NF1 gene. Neurofibromin insufficiency may induce abnormal proliferation of Schwann cells in composite pheochromocytomas as well as in neurofibromatosis.